Investigating the mechanism of infrared emissivity control in MgO doped YSZ based ceramics

•Introducing magnesium atoms into YSZ can effectively reduce its absorption coefficient and improve its conductivity.•Doping YSZ ceramics with MgO can effectively enhance the porosity of YSZ.•Doping MgO in YSZ can significantly reduce its infrared emissivity, and the optimal doping content is 5mol%. Yttrium stabilized zirconia (YSZ) possesses notable thermal stability and high conductivity, rendering it indispensable in the realm of infrared stealth. While YSZ demonstrates relatively low emissivity within the 3–5 μm wavelength range, the escalating application temperatures of aircraft demand a further reduction in the infrared emissivity within this specific band, as per Wien displacement law. This study employs first principles calculations to establish that the strategic doping of YSZ with Mg atoms effectively diminishes the absorption coefficient and enhances the material's conductivity. Based on these computational results, YSZ samples doped with varying concentrations of MgO were prepared via high-temperature solid-state reactions. Subsequently, the effects of different MgO doping levels on the microstructure, crystal structure, and infrared emissivity of YSZ were thoroughly examined. The findings indicate that as the MgO content increases, the porosity and grain size of the YSZ ceramic gradually escalate. Concurrently, the lattice constant and crystal plane spacing of YSZ experience reductions. Notably, when the doping quantity reaches 5mol%, the infrared emissivity of YSZ diminishes to its minimum level owing to the combined influences of microstructure, optical properties, and conductivity. Specifically, the emissivity within the 2–14 μm wavelength range decreases from 0.336 to 0.296.